The present invention relates in general to thiophosphine compounds (also named phosphine sulfide compounds) and their use for making polymerizable compositions which after polymerisation give optically transparent articles, such as ophthalmic lenses, having improved mechanical and optical properties and in particular having an improved UV cut.
The use of polymerizable compositions comprising thiourethane monomers is well known for making ophthalmic lenses. The thus obtained ophthalmic lenses exhibit a unique combination of mechanical and optical properties.
Nevertheless, there is still a need for improved materials for making ophthalmic lenses and in particular for materials having an improved UV cut, without adversely affecting the other required mechanical and optical properties.